On his twenty-second birthday, Nick is dying from a cursed underworld mark. His late guardian leaves him one chance: offer a silver coin to the “Queen of the Underworld.” But the one who answers is Hades himself, a silver-haired god who seals Nick’s life with a black wedding ring. Every time Hades saves him, their marriage contract grows deeper—and Nick becomes harder to let go. When a fallen priest kidnaps Nick to force Hades to open the Underworld Gate, Nick must choose: escape the god who owns his heartbeat, or claim him as an equal.